Tuning machine backplate



FIG. 1 is a perspective view of my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left-side view thereof;

FIG. 5 is a right-side view thereof;

FIG. 6 is a first end view thereof; and,

FIG. 7 is a second end view thereof.

The broken lines are for the purpose of illustrating portions of the tuning machine backplate that form no part of the claimed design. 

CLAIM The ornamental design for a tuning machine backplate, as shown and described. 